Question

get_post_custom_keys( int $post_id )

Retrieve meta field names for a post.

---

description

If there are no meta fields, then nothing (null) will be returned.

---

参数

$post_id

(int) (Optional) Post ID. Default is ID of the global $post.

---

返回值

(array|void) Array of the keys, if retrieved.

---

源代码

File: wp-includes/post.php

function get_post_custom_keys( $post_id = 0 ) {
	$custom = get_post_custom( $post_id );

	if ( !is_array($custom) )
		return;

	if ( $keys = array_keys($custom) )
		return $keys;
}

---

更新日志

Version	description
1.2.0	Introduced.

---

相关函数

Uses

• wp-includes/post.php: get_post_custom()

---

Used By

• wp-includes/post-template.php: the_meta()
• wp-includes/class-wp-embed.php: WP_Embed::delete_oembed_caches()

---

User Contributed Notes

1. Skip to note content You must log in to vote on the helpfulness of this noteVote results for this note: 0You must log in to vote on the helpfulness of this note Contributed by Codex

   Default Usage
   The following example will set a variable ($custom_field_keys) as an array containing the keys of all custom fields in the current post, and then print it. Note: the if test excludes values for WordPress internally maintained custom keys such as _edit_last and _edit_lock.

   
   <?php
   
   $custom_field_keys = get_post_custom_keys();
   foreach ( $custom_field_keys as $key => $value ) {
       $valuet = trim($value);
       if ( '_' == $valuet{0} )
           continue;
       echo $key . " => " . $value . "<br />";
   }
   ?>
   

   If the post contains custom fields with the keys mykey and yourkey, the output would be something like:

   
   0 => mykey
   1 => yourkey
   

   Note: Regardless of how many values (custom fields) are assigned to one key, that key will only appear once in this array.